private void InitDistance()
        {
            distanceUnits = new ObservableCollection <string>(Enum.GetValues(typeof(DistanceUnit)).Cast <object>().Select(value => (string)converter.Convert(value, null, null, null)));

            if (GisEditor.ActiveMap.MapUnit == GeographyUnit.DecimalDegree)
            {
                DistanceUnits.Insert(0, "Decimal Degrees");

                SelectedDistanceUnit    = DistanceUnits[0];
                SimplificationTolerance = 0.01;

                IsDecimalDegrees = true;
            }
            else
            {
                SelectedDistanceUnit    = converter.Convert(DistanceUnit.Kilometer, null, null, null).ToString();
                SimplificationTolerance = 5;
            }
        }